In the construction of naturally lit structures (e.g., greenhouses, pool enclosures, conservatories, stadiums, sunrooms, and so forth), glass has been employed in many applications as transparent structural elements, such as, windows, facings, and roofs. However, polymer sheeting is replacing glass in many applications due to several notable benefits.
One benefit of polymer sheeting is that it exhibits excellent impact resistance compared to glass. This in turn reduces maintenance costs in applications wherein occasional breakage caused by vandalism, hail, contraction/expansion, and so forth, is encountered. Another benefit of polymer sheeting is a significant reduction in weight compared to glass. This makes polymer sheeting easier to install than glass and reduces the load-bearing requirements of the structure on which they are installed.
In addition to these benefits, one of the most significant advantages of polymer sheeting is that it provides improved insulative properties compared to glass. This characteristic significantly affects the overall market acceptance of polymer sheeting as consumers desire structural elements with improved efficiency to reduce heating and/or cooling costs. Although the insulative properties of polymer sheeting are greater than that of glass, the thermal insulation value (U value) for a polymer sheet is limited by the number of air cavities as well as the solid polymer content in the sheet. Thus, there is a continuous demand for further improvement.